Explain why Martin Luther was excommunicated from the Catholic Church in the 1500's. What were some of the consequences of his actions? Include if you think your freedoms have been affected because of his life.

Martin Luther became a heretic according to the Catholic Church when he posted his Ninety-Five Theses on the church doors at Wittenberg. It was a common practice to post an academic challenge for others to read on the community bulletin board, i.e., the church doors. At the same time Luther posted his Theses, he sent a copy and a letter to the archbishop who passed the Theses on to the councillors at Aschaffenburg (later known as the University of Mainz). Considering the Ninety-Five Theses heretical, the councillors sent a copy to the pope, i.e., the Bishop of Rome.  
As was customary in academic circles of the 16th century, John Tetzel proposed his own anti-theses to Luther’s “innovations” in opposition to the “traditional teachings of the church.” To defend his Ninety-Five Theses from Tetzel’s anti-theses, Luther wrote the Resolutiones, which he sent to Bishop Scultetus of Brandenburg. Bishop Scultetus recommend that Luther keep silent and abstain from further writing on the subject fearing for Luther's standing in the Church. Luther agreed but “a new source of contention arose” in the person of Johann Eck, Vice-Chancellor of the University of Ingoldstadt. Under the direction of Bishop von Eyb of Eichstatt, Eck carefully examined the Ninety-Five Theses and determined that 18 of the complaints were heretical. 
At this point, Luther was summoned by the pope to appear before the tribunal in Rome. There he was ordered to recant his heretical statements but refused saying, “I neither can nor will recant anything, for it is neither safe nor right to act against one's conscience.” 
Johann Eck’s challenges to his own understanding of scripture drove Luther from reformer to revolutionary. Luther was officially excommunicated in May, 1521, but was allowed to go home. Nevertheless, he was a wanted man. For his protection, he was kidnapped and hidden safely at Wartburg Castle by Prince Fredrick of Saxony. That, though, was not the end of the issue; the consequences of Luther's "reform movement" were many.
The most significant consequence of Luther’s protest would ultimately be the Protestant Reformation which destroyed Christian unity forever. The Universal, i.e., Catholic, Church, no longer held sway over all of Christendom, as Christian Europe was called, and it would never be able to reunite Christians under a universal Christian Church again. The World Christian Encyclopedia says there are 33,000 Christian denominations worldwide but some say only about 9,000 are protestant denominations.
Other serious consequences of Luther's movement are as follows:
The excommunication trial resulted in the Edict of Worms (1521) which officially banned reading or having possession of any of Martin Luther’s writings. It was never fully enforced in Germany, but numerous “heretics” were burned at the stake in the Low Countries (Belgium, Luxembourg and the Netherlands). 
Peasant Wars that had been going on in the Holy Roman Empire since 1492 continued, but peasants became more aggressive and violent, driven to fever pitch by their understanding of Luther’s ideas. After emerging from his hiding place at Wartburg in 1522, Luther saw the writing on the wall — “overthrow of the State and the Church as well as property rights and family.” By 1525, the Peasant Wars resulted in victories over the nobility giving peasant leaders confidence they could win their political ambition, i.e., to reorganize the entire Holy Roman Empire. To the surprise of the peasants, Luther sided with the princes and urged them to violently stop the uprisings.
Support for Luther among German princes lead to the Peace of Augsburg in 1555 in which German Princes were given the right to determine whether their local principalities would be Catholic or Lutheran. It was not freedom of religion for everyone. Only the leaders could choose a religion, but it was the beginning of religious choice. 
Calvinism, rather than Lutheranism, was taking hold in many places in Europe including the Netherlands, Scotland and France. In France, the Edict of January, 1562, gave Huguenots, the French protestants, freedom to worship in certain cities and Edict of Nantes of 1598 officially recognized the Huguenots and provided for freedom of conscience and worship where ever French protestant churches already existed. (The Edict of Nantes was later revoked by Louis XIV.)
In 1618, the European religious wars that followed Luther’s “revolution” began a period of conflict, known as the Thirty Years’ War, that 

pitted Protestant against Catholic, the Holy Roman Empire against France, the German princes and princelings against the emperor and each other, and France against the Hapsburgs of Spain. The Swedes, the Danes, the Poles, the Russians, the Dutch and the Swiss were all dragged in or dived in.

It was one of the most destructive conflicts ever in Europe. To end the war, the Peace of Westphalia signed by the various belligerents eliminated the prospect of Catholicism ever reuniting Christendom. Along with granting autonomy for the principalities of the Holy Roman Empire, one of the main tenets of the treaties was the recognition of Calvinism along with Lutheranism as a choice for all the principalities in the HRE (about 194 princes were present at the negotiating table). 
The Counter Reformation in the Catholic Church and the English Reformation are other consequences of the Protestant Reformation in Germany. A discussion of each would be far too lengthy here.
The outcome of Luther’s challenges of the Church not only affected life for Christians then, but also for all who profess any religion today. Acceptance and tolerance emerged from Luther’s conflict with the Catholic Church, and freedom of religion is practiced and/or guaranteed in many parts of the world today.
 
http://www.christianchronicler.com/history1/spread_of_calvinism.html

http://www.newadvent.org/cathen/09438b.htm

https://www.biography.com/religious-figure/martin-luther